Improvement in processes and apparatus for manufacturing fertilizers from



ROBERT R. ZELL, OERALTIMORE, MARYLAND.

PATENT EEIcE.

IMPROVEMENT lN PROCESSES AND APPARATUS EOR MANUFACTURING FERTILIZERSFROM NIGHT-SOIL.

Specification forming part of Letters Patent No. i83,242, dated October10, 1876 application filed June 21.1876.

To all whom it may concern:

Be it known that I, ROBERT R. ZELL, of the city of Baltimore, and Stateof Maryland, have invented a certain new and useful Process forManufacturing a Concentrated Fertilizer from Night-Soil, togetherwiththe apparatus for carrying out the same, of which process andapparatus the following is a specification; and I do hereby declare thatin the same is contained a full, clear, and exact description of my saidinvention, reference being had to the accompanying drawing, and to theletters of reference marked thereon.

This invention relates, iirst, to the process of treating humanexcrement or night-soil in the manufacture of a fertilizing compound;

'l and, secondly, to the apparatus used in said process, as willhereinafter fully appear.

The whole process used in the manufacture of the fertilizer, of whichprocess the invention herein claimed forms a part, is as follows: Thenight-soil, as collected from vaults or privies, is first strainedthrough a coarse sieve, to remove extraneous substances, such vas rags,sticks, Ste., andthen placed in barrels, or other suitable receptacles,to be used as required. The said material is then, by aA secondstraining operation, divided intol two separate parts, viz., the wateryconstituents,

containing little solid matter, but rich -in ammonia and certain solublesalts, and a semifluid mass, the base of the fertilizing compound. Thewatery constituent is subjected to the action of heat sufciently intenseto drive off the ammonia, which, by Ameans of suitable' apparatus, isincorporated with the semi-fluid mass contained in a separate ves-v sel.The ammonia in the mass is fixed or ating operation, and added to thecompound.

vThe final mixing operation consists in adding to the compoundagricultural salt and muriate of potash, lafter whichthe material isthoroughly dried and ground.

, Referring to the accompanying drawing, forming `a part of thisspecification, and which represents a partially sectional side elevationof the said apparatus, A is the distilling-tank, from the upper part ofwhich extends the supply-pipe a, provided with the strainer b. Thestrainer b is reached by means of an elevated platform, to which thebarrels of primarily strained night-soil are carried by an elevator, B.`The strainer b is constructed in such manner as to allow of the passageto the distilling-tank .of the watery constituent, while the thick orheavy matter is conducted through the pipe c to one of theevaporating-tanks G.

Any desired number of the evaporatingtanks C'C C maybe employed; but inthis description one only, C, will be considered as used.

The evaporating-tankO is connected to the distilling-tank A by adraft-pipe, D, furnished with suitable valves, one of which, E, is usedto isolate the said tanks, when necessary, and has extending from, it abranch pipe, D', by means of vwhich the noxious gases and otheremanations from the matter while under treatment are carried off.l Thetanks A and C are providedwith steam-coils or worms d, connected to aboiler, by means of which worms the contents of the said tanks areheated, for purposes hereinafter described. When the evaporating-tank Gis about two-,thirds full, the strainer l) is closed tightly with acover, b', and the valves E E in the draft and supply pipes D a closed.A valve, F, in the gaspipe G, which is shown connecting the distillingand evaporating tanks, is closed, and steam` admitted to thel coil orworm d in the tank A. t Y

By this means the watery constituent of the night-soil which iscontained in the distillin'gtank is heated to the boiling-point, andammonia-vapor generated.

Strong sulphuric acid having previously been added through/pipe H to themass in the evaporating-tank'C, the valve F is opened,

which allows the ammonia-vapors to pass to `the tank C, where theincoming ammonia, to-

thereof, D', to a furnace, where it is burnedf This gas,.whenproperly-combined with-atmospheric air, may be supplied to the furnacein such manner as to assist in the generation of steam, and therebyeconomize in theconsumption of fuel.

As it s necessary, `1n order to produce a draft in the pipesiD and D',that openings should be formed near to the lowerY ends thereof, theevaporating-tank C is supplied with apertures e, through which airpasses to form the current `required to carry off the vapor andsulphureted hydrogen, tc., generated .by the action of the` heated coild in the said tank. y f

In order to retain the phosphoric acid and soluble salts, before alludedto ascontained in the liquid in thedistilling-tank A, the said liquid,after the ammonia-vapor sexpelled, is drawn oi into an evaporating-pan,(not shown,) boiled down to a thick mass, and then added to the compoundfrom the tankl C; orr

i the said liquid may be further heated by the steam until evaporated,and the phosphoric acid and soluble salts afterward removedand mixedwith the compound from the tank C. The evaporating-pan should bettedwith v a ventilated cover, and pipes leading to a flue, as in thecase of the `draft-pipe branch D. In this supplemental evaporatingprocess heat maybe applied directly to the pan, and withoutthesteam-coil. 'l

By recharging` the distilling-tank A, `and conducting the ammonia-'vaporeliminated, as before described, tothe material in the evaporating-tank(l, thepercentage of ammonia in the fertilizer may be greatly increased.

All joints in pipes through which offensive gases are conducted shouldbe closely ttcd,

and where pipes are adapted to be removable, as isthe case .with theones 0, waterluted joints should be employed.. All tanks and pipessubjected to the action ofthe sul. phuric acid should be formed'of orlinedwith some non-corrosive material. The tankGis provided with aclose-fitting door, I, on the side thereof, to be used in cleaning, anda cock through which the mass is delivered to a vat below, where thephosphoric-acid liquor d from the evaporating-pan is added.

" class to absorb the water.

To complete the process, thelmaterial iscon- Vducted through a chute,K,to a vat where the agricultural salt and muriate of potash are added,and the composition thoroughly mixed. The fertilizer is thrown into aheap orpile, and dried by` chemical heat generated therein, after whichit is ground.

The process of preparingthe fertilizer in the tankslU and C" is the sameas1th`at described in connection with the one C.

Night-soil treated in accordance with the wprocess described gives aconcentrated fertilizingcompound, asall the ammonia -in the solid orsemiiluid matter is retained, as Well as that in the liquid drawn o, andevaporated from the distilling-tank A and evaporating-pan in the form ofsulphate andv phosphate of ammonia.r i, I i .i

i The' Vsaid 4process is free from unpleasant smell, and vthe productionis anne, dry` powder, devoid' of all useless matter, such as clay,

' ashes, and the like, which are usually employediu the manufacture offertilizers ofthis Having .thus-described my invention, what Iclaim asn`ew,'and wish to secure by LettersPatentfof the United States, is

l. In the manufacture of a fertilizing compound from night-soil, theprocess consisting in separating the night-soil into watery andsemi-fluid bodies, distilling the ammoniava- `por from the said wateryconstituent, and incorporating the ammoniavapor with the semiiuid massor base ofthe fertilizing compound after thetreatment of the latter withsulphuric acid, for the purpose of fixing `the ammonia, substantially ashereinbefore specified.

l2. In an 4apparatus for treating night-soil in the manufacture of `afertilizing compound,

`the tanks A` andC, connected by the draft andgas pipes, respectively,represented by D and G, and provided withthe steam coils or worms d, invcombination with the pipe a, havin g the strainer() leading'to the saidtank A,and removable pipe c, connectingjthe said strainer indirectlywith the tank G, substantiallyas shown. i i 4 3. In an apparatus `for.treating night-soil in the manufacture of a fcrtilizingcompound,

the tank C, provided `with the apertures e, in `combination withy thedraft-pipe D and branch lD of the same, substantially as and `forlt'hethe purpose set forth.'

In testimony whereof ,I, have ,hereuntoA set my hand this 15th day ofJune, 1876.

. l, .L ROBT. It,` ZELL.

lWitnesses:vk I. SELDNER,

J. T. RoBrNsoN.

